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In the context of global change, assessing the sustainability of ecological restoration in water-scarce regions presents a critical scientific challenge. The Haihe River Basin (HRB), vital to China’s food and water security, has experienced extensive greening over the past two decades. However, the hydrological cost of this greening remains uncertain. This study leverages multi-source satellite remote sensing data (MODIS, CLCD) from 2001 to 2023 to investigate the hydrological implications of this greening. Our analysis reveals a stark ‘decoupling’: despite significant increases in Gross Primary Production (GPP) (9.45 g C·m−2·yr−1, p < 0.01), the basin-wide Water Use Efficiency (WUE) exhibited a gradual yet statistically significant decline (slope = −0.01 g C·m−2·mm−1·yr−1, p < 0.01). In contrast, Carbon Use Efficiency (CUE) demonstrated no significant basin-wide trend but exhibited significant spatial decreases in mature forest areas. Spatially, the trends are heterogeneous; while 40.80% of the basin showed improved WUE, a significant decrease was observed in only 2.88% of the area, primarily in high-productivity agricultural zones. This localized decline, however, was substantial enough (with mean rates of decrease exceeding −0.06 g C·m−2·mm−1·yr−1) to influence the basin-wide average downward. Attribution analysis identified that climate change, particularly rising temperatures and the associated increase in vapor pressure deficit (VPD), were the dominant drivers of this decline by stimulating evapotranspiration (ET) at a rate faster than GPP enhancement. Collectively, our findings suggest that the observed greening trajectory in the HRB, while increasing carbon uptake, is becoming progressively less water-efficient, indicating a path of hydrological unsustainability. This research highlights the urgent need for hydrologically informed policies in ecological restoration, shifting the focus from simple ‘greening’ towards achieving ‘sustainable and hydrologically sound greening’.

Isoxazoles and isoxazolines are five-membered heterocyclic molecules containing nitrogen and oxygen. Isoxazole and isoxazoline are the most popular heterocyclic compounds for developing novel drug candidates. Over 80 molecules with a broad range of bioactivities, including antitumor, antibacterial, anti-inflammatory, antidiabetic, cardiovascular, and other activities, were reviewed. A review of recent studies on the use of isoxazoles and isoxazolines moiety derivative activities for natural products is presented here, focusing on the parameters that affect the bioactivity of these compounds.

BackgroundThe soybean is an important food crop worldwide. Drought during the first pod stage significantly affects soybean yield, and understanding the metabolomic and physiological changes in soybeans under drought stress is crucial. This study identified the differential metabolites in initial pod stage soybean leaves under polyethylene glycol-simulated drought stress, using ultra performance liquid chromatography and tandem mass spectrometry, and the physiological indexes related to drought resistance.ResultsPhysiologically, drought resistance also generates enzyme and antioxidant activity; levels of superoxide dismutase, peroxidase, and catalase first increased and subsequently decreased, while those of soluble sugar, soluble protein, malondialdehyde, and proline content increased in both varieties. The contents of CAT, proline and soluble sugar in Heinong 44 (HN44) were higher than those in Heinong 65 (HN65), and the contents of MDA were lower than those in HN65. In metabolomics, the OPLS-DA model was used to screen different metabolites. KEGG analysis showed that the two varieties resisted drought through different ways. Amino acid metabolism and lipid metabolism play a key role in drought resistance of the two varieties, respectively. TCA cycle was one of the core pathways of drought resistance in two varieties. Changes in the content of l-Asparagine and citric acid may be one of the reasons for the difference in drought resistance between the two varieties.ConclusionsWe think that the reasons of drought resistance among soybean varieties are as follows: the main metabolic pathways are different under drought stress; the contents of metabolites in these metabolic pathways are different; some physiological indexes are different, such as MDA, CAT, proline content and so on. Our study enhances the understanding of the metabolomic soybean drought stress response and provides a reference for soybean drought resistance breeding.

Animals exhibit innate defense behaviors in response to approaching threats cued by the dynamics of sensory inputs of various modalities. The underlying neural circuits have been mostly studied in the visual system, but remain unclear for other modalities. Here, by utilizing sounds with increasing (vs. decreasing) loudness to mimic looming (vs. receding) objects, we find that looming sounds elicit stereotypical sequential defensive reactions: freezing followed by flight. Both behaviors require the activity of auditory cortex, in particular the sustained type of responses, but are differentially mediated by corticostriatal projections primarily innervating D2 neurons in the tail of the striatum and corticocollicular projections to the superior colliculus, respectively. The behavioral transition from freezing to flight can be attributed to the differential temporal dynamics of the striatal and collicular neurons in their responses to looming sound stimuli. Our results reveal an essential role of the striatum in the innate defense control. Innate defense behaviours in animals in response to approaching threats are mostly studied in response to visual stimuli. Here, the authors show that looming sounds elicit stereotypical sequential defensive reactions that require the auditory cortex, superior colliculus and the striatum.

Soybean is an important cash crop in the world, and drought is the main reason for the loss of soybean plants productivity, with drought stress during the most water-sensitive flowering period of soybeans. In this article, drought-tolerant variety Heinong 44 (HN44) and drought-sensitive variety Heinong 65 (HN65) were used as experimental materials. Drought treatment was carried out at the early flowering stage. The method of controlling soil moisture content was used to simulate different degrees of drought, and the physiological changes of these two varieties of soybean under different soil moisture contents were studied. The results showed that with a decrease in soil moisture content, the content of malondialdehyde (MDA) in soybean leaves increased significantly; the activities of peroxidase (POD), catalase (CAT), and ascorbic acid peroxidase (APX) increased first and then decreased; the content of proline, soluble sugar, and soluble protein increased; and the total antioxidant capacity (T-AOC) increased significantly. When the soil moisture content was 15.5%, the degree of membrane lipid peroxidation, osmotic regulatory substances, antioxidant enzyme activity, and T-AOC increased the most, and the decrease in drought-tolerant variety HN44 was significantly less than that of drought-sensitive variety HN65. Our research reveals the response law of soybean crops to physiological characteristics under water deficit and provides theoretical basis and guiding significance for drought-resistant cultivation and breeding of soybean.

Background Seed size is an important quality trait in crops and is one of the key factors affecting crop yield; however, how seed size affects growth and physiological differences, stress resistance, and yield characteristics is unclear. Methods In this study, the effects of different seed sizes on germination, morphology, physiological characteristics, and yield traits of soybean were studied by combining germination, pot, and field experiments using Kenfeng 16 and Heinong 84 varieties. Results The germination potential, rate, and index, as well as the vigor index of very small seeds, were significantly lower than those of other seed sizes. Plant height and leaf area followed the order: large > medium > small > very small seeds. Dry matter accumulation in each organ was significantly higher in large seeds than in small seeds. Superoxide dismutase and peroxidase activity, soluble sugar, soluble protein, and proline content were highest in large seeds, whereas malondialdehyde content was highest in very small seeds. The SPAD value (an indicator of chlorophyll content) was highest in large seeds, whereas steady-state fluorescence yield and non-photochemical quenching were higher in large and medium seeds. In terms of yield characteristics, the performance of pot experiment was basically consistent with that of field experiment. The number of pods and seeds per plant was in the order of large > medium > small > very small seeds, and no significant differences were observed in plant height, bottom pod height, node number, or internode length. The 100-seed weight and yield of the large seeds were higher than those of the small or very small seeds. Conclusions Seeds of different grain sizes have differences in germination, which may be caused by differences in seed vigor. Medium to large seeds showed better growth effects in the field, including morphological parameters, photosynthetic parameters, etc. In addition, medium to large seeds also have better resistance levels and can better adapt to the environment. These factors ultimately lead to higher yields. This study promotes the further development of the production potential of excellent varieties, and provides valuable insights for soybean seed breeding and high-yield cultivation strategies.

Drought stress is one of the most important abiotic stresses which causes many yield losses every year. This paper presents a comprehensive review of recent advances in international drought research. First, the main types of drought stress and the commonly used drought stress methods in the current experiment were introduced, and the advantages and disadvantages of each method were evaluated. Second, the response of plants to drought stress was reviewed from the aspects of morphology, physiology, biochemistry and molecular progression. Then, the potential methods to improve drought resistance and recent emerging technologies were introduced. Finally, the current research dilemma and future development direction were summarized. In summary, this review provides insights into drought stress research from different perspectives and provides a theoretical reference for scholars engaged in and about to engage in drought research.

Background Rural settlements are undergoing significant changes under the rapid urbanisation, and understanding their evolution characteristics and surrounding land use will provide a basis for land spatial planning. This study takes Pingnan County, Fujian Province, China as study area, reveals the characteristics of spatial–temporal evolution and surrounding land use transition of settlements during 1985–2020 through landscape metrics, spatial “hot spot” analysis, scale classification statistics, rank-size model, Gini index, land use transition matrix. Results The results show that: (1) Concerning the size and morphological characteristics, the settlements have witnessed a considerable increase in number and scale while remaining stable in shape. (2) Regarding spatial distribution characteristics, the settlements became more evenly spread, forming three main hotspot clusters. (3) Concerning scale structure characteristics, there are significant differences in scale, growth rates, and polarisation of settlements; the polarisation of large settlements shifted from a marked divergence before 2010 to a more balanced trend after 2010. (4) The land use transition around settlements differed in buffer zones and periods. During 1985–2010, settlement expansion heavily depended on cropland, depleting nearby resources, with an increase of woodland and grassland. During 2010–2020, expansion integrated cropland, woodland, and grassland, with cropland growth mainly encroaching on woodland and grassland. Conclusions The study's findings are significant for optimising rural settlement structure in mountains and promoting sustainable land resource use.

As manufacturing demands for challenging-to-machine metallic materials continue to evolve, the performance of cutting tools has emerged as a critical limiting factor. The synergistic application of micro-texture and coating in cutting tools can improve various properties. For the processing of existing micro-texture, because of the fast cooling and heating processing method of laser, there are defects such as remelted layer stacking and micro-cracks on the surface after processing. This study introduces a preheating-assisted technology aimed at optimizing the milling performance of textured coated tools. A milling test platform was established to evaluate the performance of these tools on titanium alloys under thermally assisted conditions. The face-centered cubic response surface methodology, as part of the central composite design (CCD) experimental framework, was employed to investigate the interaction effects of micro-texture preparation parameters and thermal assistance temperature on milling performance. The findings indicate a significant correlation between thermal assistance temperature and tool milling performance, suggesting that an appropriately selected thermal assistance temperature can enhance both the milling efficiency of the tool and the surface quality of the titanium alloy. Utilizing the response surface methodology, a multi-objective optimization of the textured coating tool-preparation process was conducted, resulting in the following optimized parameters: laser power of 45 W, scanning speed of 1576 mm/s, the number of scans was 7, micro-texture spacing of 130 μm, micro-texture diameter of 30 μm, and a heat-assisted temperature of 675.15 K. Finally, the experimental platform of optimization results is built, which proves that the optimization results are accurate and reliable, and provides theoretical basis and technical support for the preparation process of textured coating tools. It is of great significance to realize high-precision and high-quality machining of difficult-to-machine materials such as titanium alloy.

Zona incerta (ZI) is a functionally mysterious subthalamic nucleus containing mostly inhibitory neurons. Here, we discover that GABAergic neurons in the rostral sector of ZI (ZIr) directly innervate excitatory but not inhibitory neurons in the dorsolateral and ventrolateral compartments of periaqueductal gray (PAG), which can drive flight and freezing behaviors respectively. Optogenetic activation of ZIr neurons or their projections to PAG reduces both sound-induced innate flight response and conditioned freezing response, while optogenetic suppression of these neurons enhances these defensive behaviors, likely through a mechanism of gain modulation. ZIr activity progressively increases during extinction of conditioned freezing response, and suppressing ZIr activity impairs the expression of fear extinction. Furthermore, ZIr is innervated by the medial prefrontal cortex (mPFC), and silencing mPFC prevents the increase of ZIr activity during extinction and the expression of fear extinction. Together, our results suggest that ZIr is engaged in modulating defense behaviors. Zona incerta (ZI) is an inhibitory subthalamic nucleus with diverse connectivity yet its functional importance has not been extensively studied. Here the authors report that ZI receives mPFC input and can modulate both innate and learned defensive behaviors via its inhibitory projection to the PAG.